Yarn tension control device



f June 21, 1966 E, voss YARN TENSION CONTROL DEVICE 2 heets-Sheet 1Filed April 13, 1964 Edward Vossen June 21, 1966 E. VOSSEN 3,257,518

YARN TENSION CONTROL DEVICE Filed April 13, 1964 2 Sheets-Sheet 2INVENTOR. Edward Vossen BY W United States Patent 3,257,518 YARN TENSIONCONTROL DEVICE Edward Vossen, Malverne, N.Y., assignor to Stop MotionDevices Corp., Plainview, N.Y. Filed Apr. 13, 1964, Ser. No. 359,279 6Claims. (Cl. 200--61.18)

This invention relates to a yarn tension control device and one in whichthe preferred degree of tension can be selected. It constitutes animprovement over Patent No. 2,515,479 issued to the present applicant onJuly 18, 1950.

The degree of tension that is preferred in different kinds of yarn andthread, depending upon the work being done, can be established bypractice but in a large number of machines doing different work it isadvantageous to provide a device through which the yarn is passed and inwhich the preferred degree of tension can be set in advance.

It is an important object of the invention to provide a tension controldevice in which the setting of dial means will automatically conditionthe device for action when the tension departs a predetermined degreefrom the selected setting so that an alarm can be given and the.

machine operation stopped.

Another object is to provide a settable device in which the idealtension can be set and slight departures therefrom will be permittedbefore the warning signal is given or the machine stopped clue toexcessive tension or lack of tension in the yarn or thread, beyond thelimits permitted by the device.

A further object of the invention is to provide a tension device whichis operated by the yarn and will automatically adjust itself to thevarying tensions of the yarn within allowable limits without giving anysignal or stopping operation of the machine doing the knitting work.

Still further objects of the invention include the provision of means,in a compact organization, that lends itself to use in large numbers ina single machine so that each strand of yarn or thread passing from asupply spool to the needle is held separately and allowed to feed fromsupply source to work without danger of interference; to provide meansfor automatically controlling the operation of a machine when thetension of the yarn exceeds or is smaller than a predetermined amount,and to provide a device that is readily accessible to the operator, canbe adjusted with a minimum of effort and time, and provides a signal sothat the position of the detector that needs attention can be quicklylocated.

With these and other objects in view, the invention comprises certainconstructions hereinafter described and then particularly pointed out inthe claims and a preferred embodiment of the invention is illustrated inthe accompanying drawings, in which:

FIGURE 1 is a face or front view of the tension control showing thevisual setting and stop-motion warning means,

FIGURE 2 is a view in elevation taken at the left-hand end of the deviceillustrated in FIGURE 1, showing the yarn tension sensing arms,

FIGURE 3 is a view similar to FIGURE 2 taken at the opposite orrighthand end of FIGURE 1 and showing the lead-in connection from thestop-motion head clamp means,

FIGURE 4 is a top plan view of the device shown in FIGURE 1,illustrating the relative position of the tension sensing arm means,

FIGURE 5 is a view similar to FIGURE 1, with the face plate removed =toshow the interior structure of the device,

FIGURE 6 is a view in sectional elevation taken on the line 6-6 ofFIGURE 5 and illustrating the structure of the tension setting device,

FIGURE 7 is a view similar to FIGURE 2 showing an operating condition ofthe yarn tension sensing arms, and

FIGURE 8 is an enlarged view showing a modified tensional stress ordegree of slack in the yarn, passing through tension sensing arm means,visualized by an indicator marking 15 arranged to correspond with thecalibrations 14 and settable as will be later described.

The housing (FIGURE 5) in its left wall, is shaped to provide a bracket16 presenting a front face 17 and a depending end portion or strip 17A.The lower portion of the strip 17A and the end wall of the housing havejournaled therein a shaft 18 to which is suitably secured laterallyspaced tension sensing arms 19 whose rear ends are connected to acounterweight 20 to normally urge the arms 19 to a raised position asshown in FIGURE 7. Each arm, at its outer or free end has the extendedarm portion 21 thereof partly encased in a porcelain sheath 22 which isshaped to provide a foot portion 23 and a heel portion 24 rounded at thejunction to form a smooth seat for the free travel of yarn Y thereoverand through a passage defined by laterally spaced arms 25 fixed to saidfront face 17 of bracket 16 and between which said arm portions 21 canswing upwardly as shown in FIGURE 7. The fixed arms 25 are arcuatelyshaped at their outer ends as at 26 and are covered on the inside of thecurved terminal portions thereof by porcelain covers or sheaths 27 whichco-act with the sheaths 22 to form the passage above referred to. flankthe inner fixed arms 25 and in addition carry a finger 28 disposedbetween the arms 19, and movable between the arms 25, for supporting theyarn, if it should sag, in the space between said arms 19. The innerarms 25, made in one piece, are mounted on the front face 17 of thebracket 16, extend obliquely downward and are aligned laterally at theirlower ends with a third single arm 29 of like shape.

The shaft 18 extends through the adjacent end wall of the housing 11(FIGURE 5), is offset as at 31 .to carry a bearing roller 32, andprovides a contact finger 33 whose free end is arranged to engage eitherthe upper tongue 34 or the lower tongue 35 of a contact or conductorstrip 36 mounted on an insulator block 37 secured on the bottom of thehousing 11. The roller 32 underlies the free end of a tension lever 38pivoted at its opposite end in a bracket 39 secured to a wall of thehousing and biased in one direction by a coil spring 41 depending from astop pin 42 suspended in a suitable bracketfrom the top of the housing.I

The degree of tension of the yarn or thread strand is regulated veryclosely through the medium of a fine screw shaft 43 extending into thehousing 11 from the bracket 16, the bracket and end wall of the housingproviding bearings for an unthreaded portion 44 of the shaft, whichcarries a thumb-screw or adjusting means 45 at the end thereofprojecting through the depending end 17A of the bracket 16. The shaft 43carries an indicator block 46 of insulating material having a projectingfront face portion 47 on which the indicator mark 15 is printed or Thearms 19 are spaced apart and otherwise applied, the portion 47 beingadjacent the sightopening 13 in the face-plate through which the markcan be readily seen as it moves with respect to the calibrations 14. Theindicator block 46 is slotted and bored as at 48 to straddle a guideplate 49 secured at the top of the housing 11 and presenting an inclinedlower edge 51 which, at its lowest point, engages the bottom of the slotat the opposite sides of the block 46 to provide a stop for limiting themovement of the block in leftward direction. The bore portion of theopening houses a coil spring 52, a loose bearing disc 53 resting on topof the 1 spring 52, and a ball 54 which protrudes from the bottom of thebore of the block 46 and presses on top of the tension lever 38. As theblock 46 is adjusted to the left, the etfort of the roller 32 necessaryto raise the free end of the lever 38 increases to the maximum definedby the numeral 4 on the calibrated scale 14. This is the maximum forceor tension that will have to be applied by the yarn Y on the arms 19 toswing the same down to a position where the yarn will lower the tensionarms 19 and the yarn will slide otf the sheath 22 of the arm extensions21 to release the arms 19 so that they will snap to the high positionshown in FIGURE 7. As the block 46 is adjusted to the right, the effortof the roller 32 necessary to raise the free end of the lever 38decreases to the minimum defined by the cipher on the calibrated scale14. This is the minimum force or tension that may be applied by the yarnY on the arms 19 to swing the same down to a position where the yarn canslip ofi the sheath 22 of the arm extensions 21 to release the arms 19so that they will snap to the high position shown in FIG- URE 7. Theadjustment of the block 46 therefore to any position shown by theindicator permits the operator to preset the tension of the yarn desiredin accordance with the working conditions of the machine.

The counterweight 20 and the tension lever 38 coact to set the desiredtension as the resistance to the downward movement of the arms 19 isagainst the combined resistance of the counterweight and the tensionlever. As increased tension of the yarn moves the arms 19 down to apredetermined degree, the contact finger 33 of shaft 18 engages thelower tongue 35 of the contact or conductor strip 36 to complete acircuit including the housing 11, a clip 55 on strip 36 engaging themetal casing 56 of an electrical socket 57 from which a light bulb 58projects through a suitable opening in the bottom of the casing. As thearms 19 are released, when a broken end of yarn passes through, thecounterweight and tension lever action moves said arms 19 upwardly sothat the contact finger 33 of shaft 18 engages the upper tongue 34 ofstrip 36 to again complete the circuit as above described.

The circuit includes a lamp casing engaging spring contact clip 59carried in an insulator 61 extending through the end wall of housing 11and connected to another clip 62 outside the housing and to which latteris secured the end of a conductor wire 63 clamped to a current intakewire 64, terminating at its upper end in a contact arm 65. The contactarm 65 is mounted on a carrier 66 secured to the housing and which isadapted to be secured by a toggle clamp 67 to the channel member of acurrent supplying stop-motion head used for example in a knittingmachine, as shown in FIGURE 6 of Patent No. 3,001,389 granted toapplicant herein on September 26, 1961.

In addition to the control of the variation of yarn tension asaccomplished by the action of the counterweight 20 and tension lever 38,an adjustable counterweight as shown in FIGURE 8 may be used whichconsists of a mounting disk 68 carried by the ends of the extended armportions 21 of the arms 19 and beyond the shaft 18. The disk 68 hassecured thereto a counterweight 69 which is diametrically tapered toprovide relatively thick and thin arcuate portions 79 and 71respectively, and is adjustably mounted for turning movement on the disk68 by a pin 72 having a slotted head. A fine degree of counterweight maybe secured by rotating the weight 69 to bring the lighter or heavierportions thereof farther from the shaft 18 which constitutes the fulcrumof the arms 19.

When the tension of the yarn or thread, as it passes from the spools orspindles to the needles of the machine, through the settable yarntension and stop-motion control device, exceeds the amount of tensionshown by the set value, which is preferred for the type of work beingdone, the yarn starts to lower the arm 19 as the tension builds up, andwhen the finger 33 touches the flexible lower tongue 35, the circuit toa conventional stop-rnotion device or controller is closed and theknitting machine is stopped. The circuit to the lamp is also closed andthe signal given by the lamp indicates to the operator which deviceneeds attention. If the yarn should slide off the sheathed ends of arms19 the action of the counterweight and the tension lever 38 will quicklysnap the arms 19 up to cause the finger 33 to engage the upper tongue 34of the contact strip 36 with the result that the lamp circuit will againbe closed. It is immaterial that the circuit is momentarily broken whenfinger 33 disengages the lower contact strip in order to engage theupper contact strip. The machine will remain in stopped or inoperativecondition. I

When the tension of the yarn drops below the indicated preference on thedial, the arms 19 will begin to rise there being enough clearancebetween the arms 19 and 25 to permit the yarn to move in between thearms as the latter rise. When the resistance tension of the yarn hasallowed the arms to rise to the extent of causing finger 33 to engagethe tongue 34 of the strip 36, the circuit is closed, the lamp lightsand the conventional stop-motion device or controller operates to stopthe machine.

The invention is not to be restricted to the precise details ofconstruction shown since various changes and modifications may be madetherein without departing from the scope of the invention or sacrificingthe advantages to be derived from its use.

What is claimed is:

1. A machine stopping and signalling device controlled by the tension inyarn or the like travelling from a source of supply to a work station,including interfitting movable and fixed armmeans about which the yarntravels, a shaft connected to and operable by said movable arm means,having an offset roller portion and a contact finger, spaced contactmeans adapted to be connected into a machine controlling signal circuitand between which contact means said contact finger moves to engageeither contact means to complete said circuit, spring urged lever meanshaving a free end in yieldable engagement with said roller portionbiasing'the movable arm means up wardly against the resistance of saidyarn tension, and indicator means adjustable lengthwise of said levermeans applying pressure thereto to vary the resistance of said movablearm means to movement bythe yarn, said movable and fixed arm means beinglaterally spaced and being shaped to provide a yarn passage, and saidmovable arm means presenting foot portions off which the yarn may slidewhen the tension thereof exceeds a desired limit, and counterweightmeans biasing the action of said movable arm means to raised position.

2. A machine stopping and signalling device according to claim 1 inwhich said indicator means includes adjustable threaded shaft means, "anindicator block threaded to said shaft and movable therealong lengthwiseof said lever means, a spring pressed ball means in the block engagingwith the lever means to apply downward pressure to the free end thereofand stop guide means arresting the travel of said block in oppositedirections and indicating the upper and lower limits of tensionresisting force to be applied to the moving arm means by said lever.

3. A device controlled by the tension of yarn comprising a metallichousing, movable and fixed arm means mounted on said housing forengagement by said yarn, a shaft supporting the movable arm meansextending into said housing and having offset roller carrying and fingerportions, a tension lever spring biased at one end and overlying saidoffset roller carrying portion at its free end, spaced contact meansbetween which said finger portion moves when t e movable arm means movesup and down, said tension lever biasing the operation of the movable armmeans upwardly to yieldably resist the tension of the yarn passingthereover, means varying the biasing force of said tension leverincluding indicator block means, a threaded shaft extending into saidhousing and along which said block means moves lengthwise of saidtension lever, yieldable pressure means extending from said blockengaging with said tension lever, a cover for said housing having asight opening and a calibrated scale adjacent the sight opening, anindicator marking on said block visible through said sight opening andcoacting with said scale to indicate the desired degree of tension inthe yarn passing over said movable arm.

4. A device controlled by the tension of yarn as set forth in claim 3including counterweight means on said movable arm means biasing themovable arm means for 25 further upward movement in addition to andbeyond the biasing action of said tension lever.

5. A device controlled by the tension of yarn as set forth in claim 3including counterweight means on said movable arm means biasing themovable arm means for further upward movement in addition to and beyondthe biasing action of said tension lever, and means for adjusting saidcounterweight to vary said biasing action thereof.

6. A machine stopping device according to claim 1 in which saidcounterweight means includes means for adjusting the counterweight meansfor varying the biasing action of said counterweight means.

References Cited by the Examiner UNITED STATES PATENTS Wachsman et al.200-61.18 X

BERNARD A. GILHEANY, Primary Examiner.

T. D. MACBLAIN, Assistant Examiner.

1. A MACHINE STOPPING AND SIGNALLING DEVICE CONTROLLED BY THE TENSION INYARN OR THE LIKE TRAVELLING FROM A SOURCE OF SUPPLY TO A WORK STATION,INCLUDING INTERFITTING MOVABLE AND FIXED ARM MEANS ABOUT WHICH THE YARNTRAVELS, A SHAFT CONNECTED TO AND OPERABLE BY SAID MOVABLE ARM MEANS,HAVING AN OFFSET ROLLER PORTION AND A CONTACT FINGER, SPACED CONTACTMEANS ADAPTED TO BE CONNECTED INTO A MACHINE CONTROLLING SIGNAL CIRCUITAND BETWEEN WHICH CONTACT MEANS SAID CONTACT FINGER MOVES TO ENGAGEEITHER CONTACT MEANS TO COMPLETE SAID CIRCUIT, SPRING URGED LEVER MEANSHAVING A FREE END IN YIELDABLE ENGAGEMENT WITH SAID ROLLER PORTIONBIASING THE MOVABLE ARM MEANS UPWARDLY AGAINST THE RESISTANCE OF SAIDYARN TENSION, AND INDICATOR MEANS ADJUSTABLE LENGTHWISE OF SAID LEVERMEANS APPLYING PRESSURE THERETO TO VARY THE RESISTANCE OF SAID MOVABLEARM MEANS TO MOVEMENT BY THE YARN, SAID MOVABLE AND FIXED ARM MEANSBEING LATERALLY SPACED AND